PASADENA, Calif. -- NASA's Mars Odyssey orbiter heard no signal from the Phoenix Mars Lander when it listened from orbit while passing over Phoenix 60 times last week.

Odyssey had also listened for a signal from Phoenix during periods in January and February. During the third campaign, April 5 through April 9, the sun stayed above the horizon continuously at the arctic site where Phoenix completed its mission in 2008.

The solar-powered lander examined ice, soil and atmosphere at the site for two months longer than its planned three-month mission before succumbing to seasonal decline in sunlight. It was not designed to withstand winter conditions. However, in case it did, NASA has used Odyssey to listen for the signals that Phoenix would have transmitted if abundant spring sunshine revived the lander.

"In the unlikely event that Phoenix had survived the harsh Martian arctic winter and been able to achieve a power-positive state with the return of continuous sunshine, there is a very high likelihood that one or more of these 60 overflights would have overlapped with a transmission attempt by the lander," said Chad Edwards, chief telecommunications engineer for the Mars Exploration Program at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"This was the last of our three planned Phoenix search campaigns. The Mars program will evaluate the results in hand to assess whether further action is warranted," Edwards said.